Classroom Explorations:
Characteristics of Life
Introduction: Blood Cells
Blood contains several different types of cells. Red blood cells carry oxygen to other cells. Other types of cells, such as white blood cells, or
leukocytes
, provide protection from foreign cells and infectious agents. Cell fragments called
platelets
provide protection against bleeding. The red blood cells of different animals can have different structures.
In this video, white blood cells called
granulocytes
crawl along a glass slide. White blood cells are an important part of our immune system. Disk-shaped red blood cells are also visible. The ‘spiky’ red blood cells are an artifact of the slide preparation. (The elapsed time is 7 minutes.)
A drop of blood from a fingerprick was placed on a slide, diluted slightly with saline solution, then incubated at 37° Celsius for 30 minutes. Coagulated red blood cells were washed away with saline solution. A droplet of saline with human serum was put on the remaining cells, along with a silicon rubber spacer and coverslip. Images were taken on an inverted compound microscope at 37° C with a 64x DIC objective and digital camera.